UnitType Enumeration

The type of physical quantity to be measured, for example length or force.

Namespace: Autodesk.Revit.DB
Assembly: RevitAPI (in RevitAPI.dll) Version: (


public enum UnitType
Visual Basic
Public Enumeration UnitType
Visual C++
public enum class UnitType


Member name Description
UT_Undefined Undefined unit value
UT_Custom A custom unit value
UT_Length Length, e.g. ft, in, m, mm
UT_Area Area, e.g. ft², in², m², mm²
UT_Volume Volume, e.g. ft³, in³, m³, mm³
UT_Angle Angular measurement, e.g. radians, degrees
UT_Number General format unit, appropriate for general counts or percentages
UT_SheetLength Sheet length
UT_SiteAngle Site angle
UT_HVAC_Density Density (HVAC) e.g. kg/m³
UT_HVAC_Energy Energy (HVAC) e.g. (m² · kg)/s², J
UT_HVAC_Friction Friction (HVAC) e.g. kg/(m² · s²), Pa/m
UT_HVAC_Power Power (HVAC) e.g. (m² · kg)/s³, W
UT_HVAC_Power_Density Power Density (HVAC), e.g. kg/s³, W/m²
UT_HVAC_Pressure Pressure (HVAC) e.g. kg/(m · s²), Pa
UT_HVAC_Temperature Temperature (HVAC) e.g. K, C, F
UT_HVAC_Velocity Velocity (HVAC) e.g. m/s
UT_HVAC_Airflow Air Flow (HVAC) e.g. m³/s
UT_HVAC_DuctSize Duct Size (HVAC) e.g. mm, in
UT_HVAC_CrossSection Cross Section (HVAC) e.g. mm², in²
UT_HVAC_HeatGain Heat Gain (HVAC) e.g. (m² · kg)/s³, W
UT_Electrical_Current Current (Electrical) e.g. A
UT_Electrical_Potential Electrical Potential e.g. (m² · kg) / (s³· A), V
UT_Electrical_Frequency Frequency (Electrical) e.g. 1/s, Hz
UT_Electrical_Illuminance Illuminance (Electrical) e.g. (cd · sr)/m², lm/m²
UT_Electrical_Luminous_Flux Luminous Flux (Electrical) e.g. cd · sr, lm
UT_Electrical_Power Power (Electrical) e.g. (m² · kg)/s³, W
UT_HVAC_Roughness Roughness factor (HVAC) e,g. ft, in, mm
UT_Force Force, e.g. (kg · m)/s², N
UT_LinearForce Force per unit length, e.g. kg/s², N/m
UT_AreaForce Force per unit area, e.g. kg/(m · s²), N/m²
UT_Moment Moment, e.g. (kg · m²)/s², N · m
UT_ForceScale Force scale, e.g. m / N
UT_LinearForceScale Linear force scale, e.g. m² / N
UT_AreaForceScale Area force scale, e.g. m³ / N
UT_MomentScale Moment scale, e.g. 1 / N
UT_Electrical_Apparent_Power Apparent Power (Electrical), e.g. (m² · kg)/s³, W
UT_Electrical_Power_Density Power Density (Electrical), e.g. kg/s³, W/m²
UT_Piping_Density Density (Piping) e.g. kg/m³
UT_Piping_Flow Flow (Piping), e.g. m³/s
UT_Piping_Friction Friction (Piping), e.g. kg/(m² · s²), Pa/m
UT_Piping_Pressure Pressure (Piping), e.g. kg/(m · s²), Pa
UT_Piping_Temperature Temperature (Piping), e.g. K
UT_Piping_Velocity Velocity (Piping), e.g. m/s
UT_Piping_Viscosity Dynamic Viscosity (Piping), e.g. kg/(m · s), Pa · s
UT_PipeSize Pipe Size (Piping), e.g. m
UT_Piping_Roughness Roughness factor (Piping), e.g. ft, in, mm
UT_Stress Stress, e.g. kg/(m · s²), ksi, MPa
UT_UnitWeight Unit weight, e.g. N/m³
UT_ThermalExpansion Thermal expansion, e.g. 1/K
UT_LinearMoment Linear moment, e,g. (N · m)/m, lbf / ft
UT_LinearMomentScale Linear moment scale, e.g. ft/kip, m/kN
UT_ForcePerLength Point Spring Coefficient, e.g. kg/s², N/m
UT_ForceLengthPerAngle Rotational Point Spring Coefficient, e.g. (kg · m²)/(s² · rad), (N · m)/rad
UT_LinearForcePerLength Line Spring Coefficient, e.g. kg/(m · s²), (N · m)/m²
UT_LinearForceLengthPerAngle Rotational Line Spring Coefficient, e.g. (kg · m)/(s² · rad), N/rad
UT_AreaForcePerLength Area Spring Coefficient, e.g. kg/(m² · s²), N/m³
UT_Piping_Volume Pipe Volume, e.g. gallons, liters
UT_HVAC_Viscosity Dynamic Viscosity (HVAC), e.g. kg/(m · s), Pa · s
UT_HVAC_CoefficientOfHeatTransfer Coefficient of Heat Transfer (U-value) (HVAC), e.g. kg/(s³ · K), W/(m² · K)
UT_HVAC_Airflow_Density Air Flow Density (HVAC), m³/(s · m²)
UT_Slope Slope, rise/run
UT_HVAC_Cooling_Load Cooling load (HVAC), e.g. (m² · kg)/s³, W, kW, Btu/s, Btu/h
UT_HVAC_Cooling_Load_Divided_By_Area Cooling load per unit area (HVAC), e.g. kg/s³, W/m², W/ft², Btu/(h·ft²)
UT_HVAC_Cooling_Load_Divided_By_Volume Cooling load per unit volume (HVAC), e.g. kg/(s³ · m), W/m³, Btu/(h·ft³)
UT_HVAC_Heating_Load Heating load (HVAC), e.g. (m² · kg)/s³, W, kW, Btu/s, Btu/h
UT_HVAC_Heating_Load_Divided_By_Area Heating load per unit area (HVAC), e.g. kg/s³, W/m², W/ft², Btu/(h·ft²)
UT_HVAC_Heating_Load_Divided_By_Volume Heating load per unit volume (HVAC), e.g. kg/(s³ · m), W/m³, Btu/(h·ft³)
UT_HVAC_Airflow_Divided_By_Volume Airflow per unit volume (HVAC), e.g. m³/(s · m³), CFM/ft³, CFM/CF, L/(s·m³)
UT_HVAC_Airflow_Divided_By_Cooling_Load Airflow per unit cooling load (HVAC), e.g. (m · s²)/kg, ft²/ton, SF/ton, m²/kW
UT_HVAC_Area_Divided_By_Cooling_Load Area per unit cooling load (HVAC), e.g. s³/kg, ft²/ton, m²/kW
UT_WireSize Wire Size (Electrical), e.g. mm, inch
UT_HVAC_Slope Slope (HVAC)
UT_Piping_Slope Slope (Piping)
UT_Currency Currency
UT_Electrical_Efficacy Electrical efficacy (lighting), e.g. cd·sr·s³/(m²·kg), lm/W
UT_Electrical_Wattage Wattage (lighting), e.g. (m² · kg)/s³, W
UT_Color_Temperature Color temperature (lighting), e.g. K
UT_DecSheetLength Sheet length in decimal form, decimal inches, mm
UT_Electrical_Luminous_Intensity Luminous Intensity (Lighting), e.g. cd, cd
UT_Electrical_Luminance Luminance (Lighting), cd/m², cd/m²
UT_HVAC_Area_Divided_By_Heating_Load Area per unit heating load (HVAC), e.g. s³/kg, ft²/ton, m²/kW
UT_HVAC_Factor Heating and coooling factor, percentage
UT_Electrical_Temperature Temperature (electrical), e.g. F, C
UT_Electrical_CableTraySize Cable tray size (electrical), e.g. in, mm
UT_Electrical_ConduitSize Conduit size (electrical), e.g. in, mm
UT_Reinforcement_Volume Structural reinforcement volume, e.g. in³, cm³
UT_Reinforcement_Length Structural reinforcement length, e.g. mm, in, ft
UT_Electrical_Demand_Factor Electrical demand factor, percentage
UT_HVAC_DuctInsulationThickness Duct Insulation Thickness (HVAC), e.g. mm, in
UT_HVAC_DuctLiningThickness Duct Lining Thickness (HVAC), e.g. mm, in
UT_PipeInsulationThickness Pipe Insulation Thickness (Piping), e.g. mm, in
UT_HVAC_ThermalResistance Thermal Resistance (HVAC), R Value, e.g. m²·K/W
UT_HVAC_ThermalMass Thermal Mass (HVAC), e.g. J/K, BTU/F
UT_Acceleration Acceleration, e.g. m/s², km/s², in/s², ft/s², mi/s²
UT_Bar_Diameter Bar Diameter, e.g. ', LF, ", m, cm, mm
UT_Crack_Width Crack Width, e.g. ', LF, ", m, cm, mm
UT_Displacement_Deflection Displacement/Deflection, e.g. ', LF, ", m, cm, mm
UT_Energy Energy, e.g. J, kJ, kgf-m, lb-ft, N-m
UT_Structural_Frequency FREQUENCY, Frequency (Structural) e.g. Hz
UT_Mass Mass, e.g. kg, lb, t
UT_Mass_per_Unit_Length Mass per Unit Length, e.g. kg/m, lb/ft
UT_Moment_of_Inertia Moment of Inertia, e.g. ft^4, in^4, mm^4, cm^4, m^4
UT_Surface_Area Surface Area, e.g. ft²/ft, m²/m
UT_Period Period, e.g. ms, s, min, h
UT_Pulsation Pulsation, e.g. rad/s
UT_Reinforcement_Area Reinforcement Area, e.g. SF, ft², in², mm², cm², m²
UT_Reinforcement_Area_per_Unit_Length Reinforcement Area per Unit Length, e.g. ft²/ft, in²/ft, mm²/m, cm²/m, m²/m
UT_Reinforcement_Cover Reinforcement Cover, e.g. ', LF, ", m, cm, mm
UT_Reinforcement_Spacing Reinforcement Spacing, e.g. ', LF, ", m, cm, mm
UT_Rotation Rotation, e.g. °, rad, grad
UT_Section_Area Section Area, e.g. ft²/ft, in²/ft, mm²/m, cm²/m, m²/m
UT_Section_Dimension Section Dimension, e.g. ', LF, ", m, cm, mm
UT_Section_Modulus Section Modulus, e.g. ft^3, in^3, mm^3, cm^3, m^3
UT_Section_Property Section Property, e.g. ', LF, ", m, cm, mm
UT_Structural_Velocity Section Property, e.g. km/h, m/s, ft/min, ft/s, mph
UT_Warping_Constant Warping Constant, e.g. ft^6, in^6, mm^6, cm^6, m^6
UT_Weight Weight, e.g. N, daN, kN, MN, kip, kgf, Tf, lb, lbf
UT_Weight_per_Unit_Length Weight per Unit Length, e.g. N/m, daN/m, kN/m, MN/m, kip/ft, kgf/m, Tf/m, lb/ft, lbf/ft, kip/in
UT_HVAC_ThermalConductivity Thermal Conductivity (HVAC), e.g. W/(m·K)
UT_HVAC_SpecificHeat Specific Heat (HVAC), e.g. J/(g·°C)
UT_HVAC_SpecificHeatOfVaporization Specific Heat of Vaporization, e.g. J/g
UT_HVAC_Permeability Permeability, e.g. ng/(Pa·s·m²)
UT_Electrical_Resistivity Electrical Resistivity, e.g.
UT_MassDensity Mass Density, e.g. kg/m³, lb/ft³
UT_MassPerUnitArea Mass Per Unit Area, e.g. kg/m², lb/ft²
UT_Pipe_Dimension Length unit for pipe dimension, e.g. in, mm
UT_PipeMass Mass, e.g. kg, lb, t
UT_PipeMassPerUnitLength Mass per Unit Length, e.g. kg/m, lb/ft
UT_HVAC_TemperatureDifference Temperature Difference (HVAC) e.g. C, F, K, R
UT_Piping_TemperatureDifference Temperature Difference (Piping), e.g. C, F, K, R
UT_Electrical_TemperatureDifference Temperature Difference (Electrical), e.g. C, F, K, R
UT_TimeInterval Interval of time e.g. ms, s, min, h
UT_Speed Distance interval over time e.g. m/h etc.


Some unit types represent fundamental physical quantities to be measured, for example UT_Length, UT_Area, UT_Mass, or UT_Force.

Other unit types exist to provide an alternate set of unit settings for a physical quantity. For example, UT_HVAC_DuctSize is used for measuring sizes of ducts, UT_PipeSize is used for measuring sizes of pipes, and UT_SheetLength is used for measuring distances on a piece of paper. All of those are lengths and could use UT_Length, but they are typically measured using different units or to a different degree of accuracy compared with typical lengths in a building. By using different unit types, the Units class can have different default settings for measuring values of the same physical quantity.

See Also